Liquid cleaning and sterilization method

ABSTRACT

A method of washing, microbially decontaminating, and rinsing of a lumened device (B), such as an endoscope includes positioning the device in a chamber ( 12 ) of an automated processor (A). Spray nozzles ( 102, 104, 106, 108, 110 ) within the chamber sequentially spray washing, microbial decontaminant, and rinse fluids over the device. Fluid connection ports ( 150, 152, 154 ) connect with internal passages ( 187 ) of the device for delivering the fluids thereto. Leaking connectors ( 184 ) connect the automated processor connection ports with inlet ports ( 196 ) of the device and allow a portion of the washing, decontaminant, and rinse solutions to leak from each inlet port. A computer control system ( 80 ) controls leak testing, cleaning, decontamination, rinsing, and drying stages of a cycle, which are all carried out within the chamber, obviating the need for human contact with the device during processing. A door locking and latching mechanism ( 90 ) ensures that the door remains locked during the washing, decontamination, and rinse cycle to avoid accidental injury to an operator from strong chemicals used in the system.

BACKGROUND OF THE INVENTION

The present invention relates to the decontamination arts. It findsparticular application in connection with an automated system for leaktesting cleaning, sterilizing, and drying devices for medical, dental,mortuary, and pharmaceutical applications, and the like, and will bedescribed with particular reference thereto. It should be appreciated,however, that the invention is also applicable to the decontamination ofother devices in an automated processing system.

Medical devices, such as endoscopes, and other lumened instruments, aresubjected to thorough cleaning and antimicrobial decontamination betweeneach use. During medical procedures, the devices become coated withblood and other protein-rich body fluids. If the instruments aresterilized while they are coated with these materials, the hightemperatures and/or chemicals used in the sterilization process tend tocause the materials to set as a hardened layer of biological residuethat becomes difficult to remove. Not only do such residues present abarrier to sterilant penetration, but even when sterilized, they maylater break down to form toxic substances which pose hazards to patientswhen the devices are reused.

Traditionally, such devices are often rinsed in a cleaning solution,such as an enzymatic cleaner, to remove the bulk of the blood and otherbody fluids from their surfaces. The rinsing process is generallycarried out manually by immersing the devices in a shallow tray of thecleaning solution. However, for devices such as endoscopes, the cleaningfluid may not penetrate the length of the internal lumen, leaving aportion of the endoscope to become coated with dried body fluids.Additionally, the biological materials and strong cleaners may posehazards to personnel coming into contact with them.

High temperature sterilization processes, such as steam sterilization inan autoclave, are generally unsuited to the sterilization of endoscopesbecause of the delicate components and materials from which they aremanufactured. The high temperature and pressure tend to curtail theuseful life of endoscopes, rubber and plastic devices, lenses, andportions of devices made of polymeric materials and the like. Hightemperature sterilization alone does not clean. Any body fluids that arenot removed prior to thermal sterilization are typically baked on to theinstrumentation.

Instruments which cannot withstand the pressure or temperature of theoven autoclave are often microbially decontaminated with gas, such asethylene oxide gas or hydrogen peroxide vapor. Like steam, gases do notclean, requiring a separate cleaning operation. The ethylene oxidesterilization technique also has several drawbacks. First, the ethyleneoxide sterilization cycle tends to be longer than the steam autoclavecycle. Second, some medical equipment can not be sterilized withethylene oxide gas. Third, ethylene oxide is highly toxic and canpresent health risks to workers if not handled properly.

Liquid microbial decontamination systems are now utilized for equipmentwhich can not withstand the high temperatures of steam sterilization.Peroxyacetic acid, or peracetic acid, is a useful sterilant and/ordisinfectant for a variety of applications, including disinfection ofwaste and sterilization or disinfection of medical equipment, packagingcontainers, food processing equipment, and the like. It has a broadspectrum of activity against microorganisms, and is effective even atlow temperatures. It poses few disposal problems because it decomposesto compounds which are readily degraded in sewage treatment plants.

In some situations, a technician mixes a disinfectant or sterilantcomposition with water and then manually immerses the items to bemicrobially decontaminated in the liquid composition. The high degree ofmanual labor introduces numerous uncontrolled and unreported variablesinto the process. There are quality assurance problems with technicianerrors in the mixing of sterilants, control of immersion times, rinsingof residue, exposure to the ambient atmosphere after the rinsing step,and the like. For sterilizing large, instruments, such as endoscopeswith narrow lumens, however, a large receiving tray and a considerablequantity of decontaminant solution are used to accommodate and fullyimmerse the instruments.

Integrated decontamination systems, such as peracetic aciddecontamination systems, have now been developed which provide apremeasured dose of a decontaminant in solution. Items to be sterilizedare loaded into a receiving tray of a sterilization system and acartridge of concentrated decontaminant inserted into a well. As waterflows through the system, the decontaminant, which may be accompanied bysurfactants and corrosion inhibitors, is diluted and carried to thereceiving tray.

The items to be decontaminated are typically loaded into a treatmentchamber through an opening closed by a door. It is desirable to maintaina seal between the door and the chamber, to prevent leakage ofpotentially hazardous sterilization chemicals from the chamber, and alsoto prevent ingress of potentially contaminated outside air into thechamber once the items are sterile.

Accidental opening of the door during a sterilization cycle poseshazards to operators because of the strong chemicals generally used.Typically, the door includes hinges along one side and a latch mechanismon the opposing side which holds the door securely against the chamber.With large doors, a single latch is often insufficient to maintain aseal along the length of the door. Having multiple latches increases thetime required for opening and closing the chamber.

Spraying the exterior of the instruments, while flowing decontaminantsolution through the lumens, would have advantages over full immersionof the devices in reducing the quantity of decontaminant solution used.However, because of the complex shape of endoscopes, the spray jets maynot reach all of the surfaces of the device. Additionally, interiorsurfaces of the lumened devices are not reached by the spray.

The present invention provides for a new and improved automated systemfor reprocessing endoscopes and the like which overcomes theabove-referenced problems and others.

SUMMARY OF THE INVENTION

In accordance with one aspect of the present invention, a method ofcleaning and microbially decontaminating a device is provided. Themethod includes the sequential steps of positioning the device within achamber, spraying a washing solution over the device from nozzles withinthe chamber to remove soil from exterior surfaces of the device,spraying a microbial decontaminant solution over the device from nozzleswithin the chamber to microbially decontaminate the exterior surfaces ofthe device, and spraying a sterile rinse fluid over the device fromnozzles within the chamber to rinse the exterior surfaces of the device.

In accordance with another aspect of the present invention, a method ofcleaning and microbially decontaminating an endoscope is provided. Themethod includes positioning the endoscope within a chamber, contactingthe interior surface and the exterior surface of the endoscope with awashing solution to remove soil from the device, then contacting theinterior and the exterior surfaces of the endoscope with a microbialdecontaminant solution to microbially decontaminate the endoscope. Themethod further includes contacting the interior and the exteriorsurfaces of the endoscope with a sterile rinse fluid to rinse theinterior and exterior surfaces of the endoscope and then removing theendoscope from the chamber. The contact steps are automaticallycontrolled.

One advantage of the present invention is that an endoscope or otherlumened device is cleaned and microbially decontaminated in a singleautomated process.

Another advantage of the present invention is that hazards posed topersonnel by handling contaminated devices are minimized.

Yet another advantage of the present invention is that a leak resistantclosure is created with a single latching mechanism.

A further advantage of the present invention is that the door remainslocked during a sterilization cycle.

A yet further advantage of the present invention is that a decontaminantdelivery system ensures decontamination of all exterior and interiorsurfaces of the device being decontaminated.

Another advantage of the present invention is that spraying, rather thanfully immersing large items, such as endoscopes, reduces the quantitiesof water and decontaminant, pretreatment agents, and cleaning agentsused.

Still further advantages of the present invention will become apparentto those of ordinary skill in the art upon reading and understanding thefollowing detailed description of the preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may take form in various components and arrangements ofcomponents, and in various steps and arrangements of steps. The drawingsare only for purposes of illustrating a preferred embodiment and are notto be construed as limiting the invention.

FIG. 1 is a perspective and diagrammatic view of a cleaning andantimicrobial decontamination processor according to the presentinvention;

FIG. 2 is a perspective view of the chamber of FIG. 1 with the dooropen;

FIG. 3 is a plumbing diagram of the system of FIG. 1;

FIG. 4 is a side front view of the chamber of FIG. 2;

FIG. 5 is a sectional view of a section of an endoscope showing sprayjets impinging on its outer surface;

FIG. 6 is a perspective view of the endoscope rack of FIGS. 2 and 4 withan endoscope shown in phantom;

FIG. 6A is an enlarged perspective view in partial section of a rack pegof FIG. 6;

FIG. 7 is an enlarged top view of the door latching and lockingmechanism of FIG. 1 with the door partially open;

FIG. 8 is a sectional view of the door latching and locking mechanism ofFIG. 7 with the door closed;

FIG. 9 is a top view of the door latching and locking mechanism of FIG.7 with the door closed and the latching mechanism engaged;

FIG. 10 is a side view of the cabinet of FIG. 1;

FIG. 11 is a plot showing endoscope pressure, fluid temperature, andperacetic acid concentration with time for a washing and microbialdecontamination cycle in the processor of FIG. 1; and

FIG. 12 is a perspective view of a twin cabinet embodiment of aprocessor in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to FIGS. 1 and 2, an automated liquid cleaning andantimicrobial decontamination processor or system A sequentially washesthen sterilizes or disinfects items, such as medical, dental, andpharmaceutical devices, and the like. While particular reference is madeto the cleaning and microbial decontamination of lumened instruments,such as endoscopes, it is to be appreciated that the processor A hasapplication in the cleaning and/or decontamination of a variety ofdifferent devices. The processor A is particularly suited to thecleaning and microbial decontamination of instruments which are heatlabile, i.e., those, which because of their components or materials, maybe damaged by temperatures over about 60° C.

The term “endoscope,” as used herein, should be understood to include awide variety of lumened instruments, including angioscopes,artheroscopes, laparoscopes, bronchoscopes, duodenoscopes, catheters,and the like.

The term “microbial decontamination” and other terms relating todecontaminating will be used herein to describe sterilization,disinfection, and other antimicrobial treatments which are designed todestroy microorganisms contaminating the items. The term “washing” willbe used herein to describe the physical removal of soil from the items,without necessarily destroying the microorganisms contaminating theitems.

The processor A includes at least one combined washing and microbialdecontamination cabinet 10 which defines an interior washing andmicrobial decontamination chamber 12.

Items to be washed and microbially decontaminated are loaded into thechamber 12 through an opening 14 in a vertical front wall 16 of thecabinet, closed by a door 18. Within the chamber, a fluid distributionsystem 20, comprising spray jets and connection nozzles, sprays awashing/decontaminant solution over exterior surfaces of the items anddirects the solution through internal passages of endoscopes and otherobjects with lumens. A rack 21 supports one or more endoscopes in asuitable position for optimal effective washing and decontamination bythe spray system 20. The endoscope may be loaded on to the rack prior toloading into the chamber, or the rack may be positioned in the chamberprior to attachment of the endoscope.

A collection tank or sump 22 forms the base of the cabinet 10 andreceives the sprayed washing/decontaminant solution as it drips off theitems. A high pressure pump 24 delivers the washing/decontaminantsolution under pressure to the spray system 20 through a fluiddistribution system or manifold 26.

A well or mixing chamber 30 sequentially receives doses of a cleanerconcentrate and a concentrated decontaminant. The cleaner concentratemixes with water to form a washing solution for cleaning the items priorto antimicrobial decontamination. The concentrated decontaminant ispreferably an antimicrobial agent or comprises reagents which react toform an antimicrobial agent on mixing with water. The cleanerconcentrate may be an enzymatic cleaner, or an acid or alkaline cleaner,and may include detergents, surfactants, and the like. A preferredcleaner concentrate is a pH neutral, low foaming composition, which isnot harmful to the components of the device. The cleaner concentrate andconcentrated decontaminant may be in solid or in liquid form. As shownin FIGS. 1 and 2, the well 30 is integral with the collection tank 22 ofthe chamber, although a separate well is also contemplated.

A preferred antimicrobial agent is peracetic acid, either inconcentrated liquid form, or as a reaction product of powdered reagents,such as acetyl salicylic acid and sodium perborate. A water inlet 42supplies water, typically from a municipal water system, to the well 30.The water mixes with detergents, corrosion inhibitors, pH buffers, theconcentrated decontaminant, and corrosion inhibitor, buffers, and otherselected components in the well to form wash, decontaminant, or othersolutions.

Preferably, the concentrated decontaminant, cleaner concentrate, and thecorrosion inhibitors, buffers, and other components are supplied in adisposable package or cup 44 which is positioned in the well 30 prior toa decontamination cycle. The cup 44 separately holds the measured dosesof the concentrated decontaminant and cleaner concentrate, and also apretreatment mixture of buffers, surfactants, corrosion inhibitors, andother pretreatment chemicals, in separate compartments 45, 46, and 47,respectively, for separate release into the system. In this way, theitems are first washed and then microbially decontaminated. A cup cutter48, driven by an air cylinder 49, or other suitable opening member, ispositioned at the base of the well 30 for opening selected compartmentsof the cup.

The quantity of water entering the system is regulated to provide awashing/decontaminant solution of a desired concentration in thedecontamination chamber 12.

The water is preferably passed through a microporous filter in the waterinlet line 42, which filters out particles of dirt and microorganisms. Avalve 52 in the water inlet 42 closes when the selected quantity ofwater has been admitted.

With reference also to FIG. 3, a fluid supply pathway 60 connects thewell 30, the pump 24, and the fluid distribution system 26. Thus, afluid circulation loop is provided which circulates the washing anddecontaminant solutions through the well 30, pathway 60, fluiddistribution system 26, and spray system 20. Sprayed solutions collectin the well and are pumped by the pump 22 through the pathway, fluiddistribution system, and back to the spray system 20. A heater 64,situated in the fluid supply pathway 60, heats the decontaminantsolution and optionally the washing solution and a rinse liquid to apreferred temperature(s) for effective cleaning, decontamination, andrinsing.

A computer control system 80 controls the operation of the processor A,including the pump 24, the heater 64, the valves 52, locking of the door18, and the like. The control system 80 may control one or moreadditional systems A, if desired.

A door latching and locking mechanism 90 holds the door in the closedposition against the front face of the cabinet and prevents the openingof the door during a washing and decontamination cycle. A seal member92, such as a gasket, it positioned between the door and the front face16 of the cabinet to provide a fluid tight seal at the pressures used inthe cabinet.

With reference to FIGS. 2, 3, and also to FIG. 4, the spray system 20includes several types of spray nozzles 102, 104, 106, 108, and 110,which direct the cleaning/decontaminant solutions over an endoscope Band other items within the chamber 12 for 360 degree coverage.

The pump supplies the nozzles with the washing/decontaminant fluid at apressure of about 60-80 psi. The spray nozzles 102 and 104 are locatedon left and right side walls 114, 116 of the chamber 12, respectively.These have a relatively narrow angle of spray, preferably about 45degrees, for impacting the surfaces of the endoscope at high pressure.The spray nozzles 106 are located on a rear wall 118 of the chamber.These nozzles spray over a wider angle, preferably about 120 degrees,for wider coverage, although with lesser impact than the nozzles 102,104. The spray nozzles 108 are attached to an inner surface 120 of thechamber door 18.

The spray nozzle 110 extends forwardly from the rear wall 118 of thechamber and directs cleaning fluid radially in multiple directions forwide coverage. As shown in FIG. 4, the nozzle 110 includes multiplespray heads. Six spray heads are shown, angled at 60 degrees apart, fora 360 coverage. Alternatively, spray nozzle 110 is a rotating nozzle,which is rotated through a 360 degree path to deliver solution in manydirections.

With reference also to FIG. 5, the spray nozzles 102, 104, 106, 108 areangled such that all surfaces of the endoscope B are contacted by thespray of decontaminant solution emitted from the nozzles. Specifically,each nozzle spray jet 122 strikes the endoscope surface 124 at a shallowangle θ, relative to normal to the endoscope surface. Preferably, theangle θ is less than about 45 degrees, i.e., each surface of theendoscope is struck with at least one spray jet at an angle of no morethan about 45 degrees from normal. Thus, the nozzles are angled todeliver the decontaminant/cleaning solutions at different angles. Forexample, as shown in FIG. 5, nozzle 102A is directed downwardly, whilenozzle 102B is directed upwardly. Additionally, each surface of theendoscope is no more than a maximum distance x from the closest spraynozzle, so that the endoscope receives the full force of the spray jet.Preferably, x is no more than 20 centimeters, more preferably, x is lessthan about 15 centimeters. Further, each surface of the endoscope is noless than a minimum distance from the closest spray nozzle, so that theendoscope receives the full force of the spray jet. Preferably, theminimum distance is at least 5 centimeters.

With reference once more to FIG. 3, to obtain these minimum criteria,the nozzles are in many cases positioned so closely that their spraysmay interact. The interaction, prior to contacting the instrument, cannegate or alter their force, angle of impact and other characteristics.To avoid the spray jets 122 from different directions canceling eachout, the jets are pulsed in sequence. For example, the manifold 26includes a first fluid line 130 which supplies nozzles 102 and a secondfluid line 134 which supplies nozzles 104. The controller 80sequentially opens an air diaphragm valve 138 in the first line 130 fora few seconds, allowing the cleaning/decontaminant solution to flow tonozzles 102, then opens an air diaphragm valve 140 in the second line134 for a few seconds, allowing the cleaning/decontaminant solution toflow to nozzles 104.

With reference now to FIGS. 2 and 3, the spray system 20, in addition tothe nozzles, also includes several connection ports 150, 152, and 154,for supplying washing/decontaminant solution to the internal passages ofthe endoscope B and an associated set of biopsy forceps. The differentinternal passages of a typical endoscope and biopsy forceps are rated towithstand different maximum pressure. The connection ports supplywashing/decontaminant solution at an appropriate pressure that is belowthe maximum pressure rating for the passage to which the connection portsupplies solution. For example, as shown in FIG. 3, the manifoldincludes fluid lines 160, 162, which supply fluids to connection ports150A and 150B at a first pressure, preferably of no more than about 20psi, for washing/decontaminating the lumens, and line 164, whichsupplies connection port 152 at a second pressure, preferably of no morethan about 40 psi, for washing/decontaminating the Endoscopic RetrogradeCholangiopancreatography (ERCP) passages. Another fluid line 166supplies connection port 154 at a third pressure, preferably of no morethan about 20 psi, for cleaning/decontaminating the biopsy forceps.Pressure regulators 168, 170, 172, and 174 in each of the fluid lines160, 162, 164, and 166 are set to ensure that the maximum pressure isnot exceeded. Pressure switches 176, 178, 180, 182 detect whether aminimum fluid pressure in the lines 160, 162, 164, and 166 is met.

With reference once more to FIG. 5, the connection ports 150, 152, and154 are connected with the respective internal passages of the endoscopeand biopsy forceps by tubes 180, each with a quick connect 182 at theconnection port end and a suitable connector 184 at the other end forconnecting with the inlet port 186 of the respective internal passage,for releasably and quickly connecting the fluid lines with therespective internal passages 187. To avoid confusion and accidentalover-pressurization of the lumens, the quick connects 182 for the lowpressure lines 160, 162, 166 will not connect with the high pressureconnection port 152. In the preferred embodiment, the connectors havedifferent sizing; but, different shapes and the like are alsocontemplated.

The connectors 184 are preferably leaking connectors, i.e., they allow acontrolled portion of the washing/decontaminant solution to flow betweenthe connector and the inlet port to contact all adjacent surfaces 190 ofthe inlet port 186. This ensures that all the accessible surfaces of theinternal passage 187 are contacted with the washing/decontaminantsolution. The portion of the washing/decontaminant solution which leaksfrom around the connector is only a small proportion of the solutionentering the inlet port. The majority of the solution travels along thefull length of the endoscope internal passage and out of the endoscopeinto the chamber 12.

In the embodiment of FIG. 5, the leaking connector 184 includes a metalC-ring 191. The C-ring is seated loosely in an annular groove in aportion 192 of the connector which is received past a small lip of theinlet port 186. The ring spaces the connector from the internal surfaces190 of the inlet port, allowing a portion of the fluid to flow around itand out of the inlet port 186. Other configurations of male and femaleleaking connectors are also contemplated.

With reference to FIG. 3, a further connection port 202 in the chamberconnects a leak detector 204 with the venting connector port of theendoscope for testing the endoscope for leaks. The leak detectorsupplies air under pressure to the venting connector port and itsassociated internal passage for detecting leaks from the internalpassage. If leaks are found, the leak detector aborts the cycle toprevent fluids from leaking into sensitive regions of the scope.

With reference once more to FIG. 2 and reference also to FIG. 6, therack 21 is preferably removable from the chamber 12. To accommodatedifferent types of endoscope, several racks 21 are provided, each oneconfigured for receiving a particular type or family of endoscopes. Theappropriate rack is selected according to the endoscope to be cleaned,and the endoscope fitted to the rack prior to or after hooking orotherwise attaching the rack within the chamber. The rack includes acentral rectangular support frame 205 with a carrying and connectinghandle 206 attached at an upper end thereof. Mounted on the frame aresupport members 207, 208, which are configured for receiving theendoscope operating section and light guide connector sections,respectively. Small, separate components of the endoscope, such ashoods, plugs, and other semi-reusable items, may be hung from the rackin a porous bag 209. The upper end of the rack is releasably mounted ona suitably receiving member or members 210 within the chamber.

The rack includes an arcuate portion 211 which supports a number of pegsor tabs 212. The pegs on the arcuate section and the support frame 205define a circle for support of the flexible tubes (the umbilical cableand the insertion tube) of endoscope B such that the tubes curve in awide loop on the rack 21. Preferably, the rack and hooks position theendoscope such that it is not bent sharper than its minimum bend radius.In the preferred embodiment, the bend radius is at least 15 centimeters,i.e., no portion of the flexible portions of the endoscope tubes arebent into a curve which has a radius of less than about 15 cm. Thisensures that as the endoscope is wrapped around the pegs 212 it iscorrectly positioned for receiving the full force of the spray jets andthat there are no inaccessible or potentially damaging tight bends inthe endoscope. Depending on the stiffness of the flexible tube, the tubeis mounted inside and/or over the pegs. The pegs are positioned atangular intervals such that the end of the tube of every endoscope inthe family ends up near, but just beyond, one of the pegs.

The rack is preferably formed from stainless steel or other materialswhich are resistant to the decontaminant solution and other chemicalsemployed in the chamber.

To minimize contact with the endoscope, and improve access of the sprayof washing or decontaminant solutions to the contact areas, the supportmembers 207, 208, and pegs 212, preferably make only “point contact”with the endoscope, i.e., the area of contact is as small as ispossible, without resulting in damage to the endoscope. In one preferredembodiment, the pegs and support members are formed from ascrew-threaded stock, which contacts the endoscope only at tips 213 ofthe threads, as shown in FIG. 6A. Preferably, the tips of the threadsare blunted, such as acme threads or threads with a sinusoidal or othercurved cross section, to avoid indentation, scratching, or other damageto the endoscope. A clip 214 holds a tip of the endoscope against therack.

The rack 21 further includes pegs 228 for supporting coiled biopsyforceps which are designed to pass through a channel of the endoscope.To anchor the forceps more securely, they are preferably coiled on acarrier which is supported on pegs 228.

With continued reference to FIG. 1 and reference also to FIGS. 7, 8, and9, the door latching and locking mechanism 90 includes a latchingmechanism 238, which holds the door 18 closed. The latching mechanism238 includes at least two and preferably four latching arms240,242,244,246. Each of the latching arms is pivotally connected to adevice 250 which is rigidly mounted to a rear wall 252 of the cabinet.Each of the arms includes a flat plate 254 which is pivotally connectedto the clevis at a pivot point 256. The plate 254 extends horizontallyforwardly from the pivot point 256, adjacent a side wall 258 of thecabinet. The latching arms 240,242,244,246 extend forwardly of the frontface 16 of the cabinet, through suitably positioned slots 260 in thefront wall. FIG. 2 shows the slots, but with the latching arms omittedfor clarity. One or more rollers 264 (three are shown in FIG. 1) isvertically mounted between pairs of forward ends 266 of the latchingarms. The rollers 264 rotate about a vertical axis.

Vertically mounted on a front face 270 of the door, adjacent the doorlatching mechanism 238, is an engagement member 272 with a verticallyextending camming surface 274 having an L-shaped cross section. When thedoor 18 is in the closed position, as shown in FIG. 8, the latchingmechanism 238 can be manually, or automatically pivoted about the pivotpoints 256 in the direction of arrow E from the disengaged positionuntil the rollers 264 engage the camming surface 274. The cammingsurface is preferably formed from rubber or other suitable rigidmaterial. In the engaged position (FIG. 9), the rollers 264 hold thedoor 18 firmly against the front face 16 of the cabinet. In thisposition, the compression seal 92 is compressed between the door and thecabinet, creating a seal around the opening 14 of the chamber.

With reference to FIGS. 1, 8, 9, and also to FIG. 10, the door latchingand locking mechanism 90 also includes a locking mechanism 280, which isactuated by the control system 80 when the latching arms 240,242,244,246are in the latched position (FIG. 9). The locking mechanism 280preferably includes a piston rod 282 actuated by an air cylinder 284. Inthe locked position, the rod 272 extends vertically upward from the aircylinder and engages at least one of the latch arms 242 as shown in FIG.10. This prevents outward movement of the latch arm and disengagement ofthe rollers 264 from the engagement member 272. The rod is retracted toan unlocked position before the latching mechanism 238 can be disengagedand the door 18 opened.

Preferably, the latching mechanism 238 includes a supporting member 290,such as a vertically extending wire shaft which connects each of thelatching arms 240, 242, 244, 246 together as shown in FIG. 10. The shaft290 passes through suitably positioned apertures each of the latchingarms in turn and is held in tension by upper and lower nuts 292, 294.Blocks 296, each having a central bore, are mounted on the shaft,between pairs of the latching arms, to space the latching arms asuitable distance apart. Thus, the supporting member ensures that eachof the latching arms moves generally together, while allowing a limitedamount of relative freedom of movement to compensate for minordifferences in the width of the door, and the like.

With particular reference to FIG. 7, which shows the door in thepartially open position, a latch arm stop 300 is mounted on at least oneof the latching arms 240. The latch arm stop 300 extends horizontallyfrom adjacent the forward end of the latching arm, towards the side 258of the cabinet and includes a downwardly protruding stop 302, formedfrom rubber or other resilient material. The stop limits the outwardmovement of the arm by engaging a rearwardly extending flange 304 whichis connected to the front wall 16 of the cabinet.

With reference to FIG. 8, a sensor system detects whether the door isproperly latched and locked. The sensor system includes a first sensor310, mounted on the forward end 266 of one of the latching arms, thatsenses that the latching arm is properly positioned adjacent theengagement member 272. The sensor 310 signals the control system 80 whenthe sensor is closely spaced from the engagement member 272, as shown inFIG. 9. A second sensor 312 forms a part of the locking mechanism. Thesecond sensor detects whether the piston rod 282 is extended, andtherefore engaging the latch arm plate 254, and signals the controlsystem.

In a typical decontamination cycle, items to be decontaminated are firstinserted into the cabinet 10 through the opening 14, with the door 18open, as shown in FIG. 2. The endoscope B to be cleaned is mounted onthe rack 21 and inserted into the chamber 12 with other items to becleaned and decontaminated. The tubes 180 are connected with theirrespective endoscope inlet ports 186 and connection ports to connect theendoscope internal passages with the fluid lines. The biopsy forceps areloaded on the rack 21. The leak detector 204 is connected with theendoscope venting connector port. A fresh cup 44 of concentrateddecontaminant and other components is inserted into the well 30 and arestraining member or lid 314 positioned over the cup.

Once all the items are properly positioned and fluid lines connected,the door 18 is brought into the closed position, as shown in FIG. 8. Thelatching mechanism 238 is then pivoted around the pivot points 256 untilthe rollers 264 engage the camming surface 274 as shown in FIG. 9,indicating that the door is fully closed and fully latched. As thelatching mechanism is moved from the disengaged to the engaged position,the geometry of the camming surface, the rollers, and the arm pivotpoint, along with the spring energy provided by the compression seal,result in the final positioning of the rollers being “over center.”

The sensor 310, mounted on the forward end of the forward end of thelatching arm, senses that the latching arm is properly positionedadjacent the camming surface and signals the control system 80 that thelatching mechanism is engaged. The control system then signals the aircylinder 284 to move the piston rod 282 from a lowered, or unlockedposition to the locked position, such that the piston rod engages theouter side of the latch arm plate 254. The sensor 312 in the lockingmechanism detects that the piston rod is in the locked position, andsignals the control system 80 that the latching mechanism is locked inposition. The control system does not commence a washing anddecontamination cycle until the sensors 310, 312 register that thelatching mechanism 238 is properly engaged and that the lockingmechanism 280 is in the locked position. At the end of the cycle thecontrol system signals the locking mechanism to retract the locking rod.The latching mechanism can then be withdrawn from engagement with thecamming surface.

With reference to FIG. 3 and also to FIG. 11, the entire process,including door locking, leak testing, washing, microbialdecontamination, and rinsing steps, is fully automated. There is no needfor an operator to contact the items until all of the steps arecomplete. As shown in FIG. 10, a typical cycle includes five phases, aleak testing phase I, a prerinse and washing phase II, a microbialdecontamination phase III, a rinse phase IV, and a drying phase V, whichare carried out in sequence.

In phase I, the control system 80 signals the leak tester 204 to checkthe endoscope for leaks. If all is satisfactory, phase II begins. Thecontrol system can be programmed to skip this step, if, for example, thedevice does not have an internal passage to be tested, or if timeconstraints make it desirable to reduce the overall cycle time.

In phase II, the items are preferably subjected to a prerinse operation,stages IIb-IId, in which the items are sprayed externally and flushedinternally with warm (about 30-35° C.) water for about one minute toremove the bulk of surface contamination. The temperature of the wateris selected to prevent protein denaturation. Denatured proteins adhereto surfaces and are difficult to remove. Accordingly, the water is keptbelow 35° C. to prevent this denaturation. All of the soil and otherdebris which is rinsed off the device is captured in a filter 318, suchas a backwashable drain strainer, and is not recirculated through thefluid distribution system. During drain portions of the cycle, thefilter is flushed to remove debris.

After about 1 minute of prerinsing, the control system signals a drainvalve 240 in the fluid line 60 to open and the rinse water is flushedfrom the system A to the drain.

In stage IIe, the endoscope is flushed with air. Specifically, thecontrol system 80 signals a valve 320 in an air line 322 to open andsupply microbe-free compressed air to the system to remove excess waterfrom the items. The air is preferably passed through a HEPTA microberemoval filter 324 before entering the system.

In stage IIg, the computer control 80 signals the valve 52 in the waterinlet line 42 to open, allowing water to circulate through the well andthe fluid lines 60. In stage IIh, the heater 64 heats the water to asuitable temperature for cleaning. The temperature selected is withinthe range of temperature to which the device may be subjected, whileproviding effective cleaning. For endoscopes which have a maximum ratingof 60° C., that are being cleaned with a detergent based washingsolution, a preferred washing solution temperature is from about 48-52°C. If an enzymatic cleaner is to be used, the temperature selected willalso depend on the stability and operating temperatures of the enzymesemployed.

In stage IIj, the computer control system 80 signals the opening member48 to open the cleaner compartment 46 of the cup. The cleanerconcentrate mixes with the water to form the washing solution and isdelivered by the pump 22 under pressure to the nozzles 102, 104, 106,108, 110 and endoscope connection ports 150, 152, 154, 156 in stage IIk.The nozzles spray the washing solution over the outer surfaces of theitems while the connection ports deliver the solution to the internalpassages, thereby cleaning inner and outer surfaces simultaneously.Sprayed washing solution, which drips off the items, is collected in thesump 22. The pump 22 returns the collected solution from the sump to thefluid supply line 60, preferably after first passing at least a part ofthe collected solution through the well 30 to ensure complete mixing ofthe concentrated cleaner in the solution. A sensor 328, such as aconductivity detector detects whether there is concentrated cleaner inthe washing solution, for example, by measuring the conductivity of thecirculating washing solution.

The washing solution removes soil from the items, leaving them clean,but not necessarily free of viable microorganisms. The spray jets areparticularly effective in this physical cleaning stage.

If the instruments to be cleaned have been left for a relatively longperiod between use and processing (greater than about an hour), it ispreferable to use an enzymatic soak prior to, or in place of, thewashing phase. This helps to loosen the blood and other proteins, whichgradually harden and become difficult to remove. The enzymatic soakpreferably lasts from about 10 minutes to about an hour. In the soak,the enzymatic washing solution is circulated slowly through the system.An additional compartment may be provided in the cup 44, if enzymaticcleaning as well as detergent washing steps are to be used. The controlsystem 80 is programmable to provide for an enzymatic soak in place of,or in addition to, a normal washing step.

Once the washing solution has been circulated through the system forsufficient time to remove all or substantially all of the soil from theendoscope and other items the control system signals a drain valve 330in the fluid line 60 to open and the washing solution is flushed fromthe processor A to the drain. Optionally, in stage Ill, the water inletvalve 52 is opened to allow additional fresh water into the system toflush the washing solution from the fluid lines 60,24 and the well 30.The drain valve 330 is then closed. Another air flush/drying step ispreferably carried out as stage IIm to remove excess water from theitems. In stage IIn-s, an additional hot water rinse and dry isoptionally carried out.

Optionally, the devices are manually cleaned, rather than being washedin the processor A. In such cases, the operator programs the controlsystem 80 to skip the washing and optionally the rinsing steps IIj-s. Acup 44 which lacks the compartment holding the concentrated cleaningagent is also provided.

In stage IIIa-c, the control system 80 opens the valve 52 for a shortperiod to allow more water into the processor and signals the heater toheat the water. Once sufficient water has entered the system forcarrying out the decontaminant part of the cycle, the controller 80signals the valve 52 to close. The control system 80 signals the cupcutter 48 to open the second compartment 47 of the cup 44, containingthe pretreatment components (stage IIId). These are released into thefluid lines and are circulated through the processor as a pretreatmentsolution. The pump 22 circulates the pretreatment solution so that thepretreatment chemicals are distributed throughout the processor A andover the items to be microbially decontaminated, prior to admission ofthe decontaminant. The buffers present buffer the water in the fluidlines to an appropriate pH (typically pH 5-9) for effectivedecontamination. The corrosion inhibitors present coat the parts of theprocessor to be exposed to the decontaminant solution and the surfacesof items to be decontaminated with traces of inhibitors to provideresistance to the corrosive effects of the decontaminant.

Although the pretreatment components may be alternatively included inone or other of the cleaner and decontaminant compartments 46,45 theireffectiveness is less there than if used as intermediate pretreatments.If the pretreatment components are not released into the processor Aprior to the decontaminant, for example, they do not have time tocirculate through the system prior to addition of the microbialdecontaminant. In the case of inhibitors, for example, their function isto provide protection for the system, and items to be microbiallydecontaminated, against the corrosive components of the microbialdecontaminant. By releasing corrosion inhibitors before the microbialdecontaminant, the inhibitors are assured time to develop protectivebarriers around the parts before the parts are contacted by thedecontaminant. In the case of buffers, their function is to modify thepH of the fluid circulating in the system so that the pH is optimal formicrobial decontamination, again near neutral with a preferred pH of5-9. Until the buffer has circulated throughout the system, themicrobial decontaminant is not fully effective. Additionally, suchagents may degrade the microbial decontaminant during storage.Accordingly, it is preferable to provide a separate compartment 47 forthe pretreatment components and allow them to circulate through thesystem for a period of time before introducing the decontaminant.

After a preselected period of circulation, the controller 80 signals thecutter assembly to open the third compartment 45 (stage IIIe). Thedecontaminant then mixes with the pretreatment components in the fluidlines 60, 24 and is sprayed through the nozzles 102, 104, 106, 108, 110and delivered to the endoscope connection ports 150, 152, 154, 156, sothat the decontaminant solution flows over the exterior surfaces andthrough the internal passages of the items to be decontaminated (stageIIf). The nozzles pulse the decontaminant fluid in a preselectedsequence to ensure full coverage of the spray. A decontaminant sensor332 in fluid communication with one of the fluid flow lines 60, 24optionally detects the concentration of the decontaminant in thecirculating fluid to ensure that a threshold concentration for effectivedecontamination is provided.

The control system controls the heater so that an optimum temperaturefor decontamination is maintained. Once again, the optimum temperatureis dependent on the maximum rating for the device being decontaminated,and also on the effective temperature for the decontaminant. Forperacetic acid sterilization of endoscopes rated to 60° C., a preferredminimum temperature of about 48-55° C., more preferably, about 50° C.,for the circulating decontaminant solution is maintained.

The chamber is maintained under a slight positive pressure duringdecontamination to minimize ingress of outside air into the chamber. Airexits the chamber through vents (not shown), which provide a tortuouspathway to minimize air ingress.

After a period of circulation of the decontaminant solution sufficientto effect decontamination of the items (typically about 10-15 minutesfor complete sterilization, more preferably, about 12 minutes; 2-5minutes for high level disinfection, more preferably, about 3 minutes),the drain valve 330 in the processor A is opened and the decontaminantsolution flushed from the processor A to the drain (stage IIIg). Thecirculation period is optionally adjusted in accordance with monitoreddecontaminant levels during the cycle.

The rinse phase IV then begins. The drain valve 330 is kept open and thecontrol system opens a valve 334 to allow a source 336 of sterile rinsewater to supply sterile water to the fluid lines 60 for rinsing thedecontaminated items without risk of recontamination of thedecontaminated items. The source of sterile water preferably comprises awater heater 338 which heats incoming tap water to a sufficienttemperature to destroy microorganisms (preferably about 150° C.) in thewater, and a heat exchanger 339, which transfers excess heat from thesterilized water to the incoming tap water (FIG. 3). The water heaterremoves salts from the incoming water which could otherwise deposit onthe washed and microbially decontaminated instruments. The waterproduced by the sterile water generator is thus of high purity. Thesterile water generator 336 provides water on demand, eliminating theneed to store large quantities of sterile water. The rinse phase mayinclude several fill and blow off stages (IVa-e).

Alternatively, the water inlet valve 52 is opened once more to providerinse water for rinsing the decontaminated items again.

The system A has a fill of about 9 liters. A typical cycle includes 6fills, for a total fluid requirement of 54 liters, as follows:

1) for pre-rinsing,

2) for forming the washing solution,

3) rinsing the washing solution from the system,

4) for forming the pretreatment and decontaminant solution, and

5) and 6) for sterile rinsing.

After the rinse water has been discharged to the drain, the controlsystem 80 signals the valve 320 in air line 322 to open and supplymicrobe-free air to the system to blow accumulated water out of and of fof the decontaminated items. The air line is connected with the manifold26 so that the air flows through the nozzles and connection ports,drying the interior and exterior surfaces of the endoscopes and otheritems. The regulator valves 168, 170, 172, and 174 ensure that theinternal passages of the endoscope B are not pressurized beyond theirrecommended pressure ratings.

Optionally, an alcohol flush is used in addition to, or in place of thelast of the rinse steps IV a-e. In this case, a source of alcohol 350supplies the alcohol to the chamber to remove excess water from thedevice B. Remaining alcohol quickly evaporates from the device. FIG. 3shows the source of alcohol connected with the connection ports 150,152, 154, via a pump 352 for delivering the alcohol to the internallumens of the device, although it is also contemplated that the alcoholmay be supplied to the nozzles also, for drying the exterior of thedevice.

Optionally, the device may be kept in the chamber for an extendedperiod, such as overnight, to increase water removal. Or the air used toflush the device may be heated to increase evaporation and waterremoval.

At the end of the cycle (stage VI), the controller 80 signals the cutterassembly 48 to retract from the cup 44 to its starting position and thedoor locking mechanism to disengage.

Because the steps of leak testing, washing, decontaminating, rinsing,and air drying are carried out automatically and sequentially within thechamber, the entire reprocessing cycle can be carried out in arelatively short period of time, typically 30 to 40 minutes for fullsterilization, 20-30 minutes for high level decontamination. Theendoscopes are thus ready for reuse in a much shorter time thanconventional cleaning and decontamination processes, in which anoperator carries out the reprocessing steps using a number of separatepieces of equipment.

The decontaminated items are removed from the decontamination chamber 12for immediate use or transferred to sterile pouches and stored untilneeded. The rack 21 can be used to transport the endoscope B to astorage cabinet or to a surgery. The rack handle is configured forcarrying the rack and for supporting the rack in the storage cabinet.Thus, the endoscope need not be touched until it is to be used in asurgical procedure, minimizing the potential for contamination.

Optionally, the device B is enclosed in a sterile pouch before removalfrom the chamber, to minimize airborne contamination prior to reuse. Forexample, the device may be wrapped in a bag, within the chamber, priorto opening of the door. This may be achieved by suitable controls, ormanually, for example with a glove box-type of device in which theoperator removes the various connectors from the device and wraps thedevice in the bag using sterile gloves (not shown) which extend into thechamber.

In an alternative embodiment, the chamber 12 acts as a sterile pouch andis hermetically sealed and disconnected from the rest of the processor Aand transported to the site at which the decontaminated items are to beused.

With reference to FIG. 12, a pair of the cabinets 10, 10′ are mountedside by side in a common frame 350. A control panel 352 for controllingthe cycles in both cabinets is disposed between the two cabinets. Thecontrol panel includes a touch input device 354, such as a touch screenor key pad, which an operator selects among the cycle options and inputsother commands to the control system 80. The control system controls thecycles in each cabinet independently, allowing cycles to be runasynchronously. An electronic display 356 provides real time informationto the operator about the state of the system and cycles in progress. Apair of printers provide printouts 358 descriptive of each sterilizationcycle. The printout is available to be transported with thedecontaminated endoscope for record keeping purposes. Preferably, anelectronic record is also maintained.

The cabinets 10, 10′ each have doors 18, 18′ that include largesee-through windows 360, 360′. These windows enable the operator tomonitor the inside chambers of the cabinets during and between cycles.The frame 350 includes door panels 362, 362′ that provide front accessto water filters and other service items.

Suitable concentrated cleaning agents are low foaming detergents orenzymatic cleaners, with a pH close to neutral (preferably pH 6-8), tominimize corrosion of metal components.

Various antimicrobial agents may be utilized for the decontaminant. In apreferred embodiment, the decontaminant is a solution of peracetic acid.However, it is also contemplated using other liquid or powdereddecontaminants or reagents which react in a common solvent to generateperacetic acid, chlorine, hydrogen peroxide, hypochlorous acid,hypochlorite, or other strong oxidants which have biocidal effects.Aldehydes, such as glutaraldehyde, may be used, but the decontaminantsolution should be collected after use and properly treated, rather thandisposed of via the drain.

Preferably, the pretreatment agent includes a buffer and a corrosioninhibitor. One preferred buffering system includes a combination ofmonosodium phosphate, disodium phosphate and tripolyphosphates. Such abuffering system also provides anticorrosion properties. Wetting agentsand other corrosion inhibitors may alternatively be used. Preferredcopper and brass corrosion inhibitors include azoles, benzoates, otherfive-membered ring compounds, benzotriazoles, tolytriazoles,mercaptobenzothiazole, and the like. Other anti-corrosive compoundsinclude phosphates, molybdates, chromates, dichromates, tungstates,vanadates, borates, and combinations thereof.

The corrosion inhibitory agents are selected in accordance with thenature of the materials in the items being cleaned and/or decontaminatedwith the decontaminant. Corrosion inhibitors which protect againstcorrosion of aluminum and steel, including stainless steel, includephosphates, sulfates, chromates, dichromates, borates, molybdates,vanadates, and tungstates. Some additional aluminum corrosion inhibitorsinclude 8-hydroxyquinoline and ortho-phenylphenol.

More specifically, phosphates are preferred for inhibiting stainlesssteel corrosion. Preferred phosphates include, but are not limited to,monosodium phosphate (MSP), disodium phosphate (DSP), sodiumtripolyphosphate (TSP), sodium hexametaphosphate (HMP), and sodiumsulfate either alone or in combination. Preferred borates include sodiummetaborate (NaBO₂).

Copper and brass corrosion inhibitors include triazoles, azoles,benzoates, tolyltriazoles, dimercaptothiadiazoles, and otherfive-membered ring compounds. Particularly preferred copper and brasscorrosion inhibitors include sodium salts of benzotriazole andtolyltriazole which are preferred due to their stability in the presenceof strong oxidizing compounds. Mercaptobenzothiazole can also beutilized but is apt to be oxidized or destabilized by strong oxidizers.Salicylic acid is an example of an acceptable benzoate corrosioninhibitor.

In hard water, phosphate buffers and corrosion inhibitors tend to causecalcium and magnesium salts present in the hard water to precipitate andcoat the instruments being decontaminated and/or cleaned and also leavesdeposits on parts of the system. In such cases, a sequestering agentappropriate to prevent precipitation such as sodium hexametaphosphate(HMP), or trisodium nitrolotriacetic acid (NTA Na₃) is preferablyprovided. Because sodium hexametaphosphate is also a corrosioninhibitor, it serves a dual purpose, both as a corrosion inhibitor andas a sequestering agent. Other sequestering agents include sodiumpolyacrylates. Of course, if soft or deionized water is utilized, thesequestering agent may be eliminated. However, to ensure universalapplicability with any water that might be utilized, the presence of asequestering agent is preferred.

A surface energy reducing agent (surfactants/wetting agents) ispreferably agents to increase penetration into crevices of items beingtreated. This is particularly important when cleaning anddecontaminating complex medical instruments which may contain microbialcontaminants in crevices, joints, and lumens. Surface energy reducingagents usable in accordance with the present invention include anionic,cationic, nonionic, amphoteric, and/or zwitterionic surfactants.Specific classes of surfactants which are useful include anionic andnonionic surfactants or combinations thereof. Examples of nonionicsurfactants usable in the present invention include surfactants such asfatty alcohol polyglycol ethers, nonylphenoxypoly (ethyleneoxy) ethanol,and ethoxylated polyoxypropylene. Specific examples include GenapolUD-50™, Igepal™, Fluowet™, and Pegal™. The surfactants set forth abovemay be used alone or in combination with each other.

Amounts of the corrosion inhibitors and surfactants to be used in theperacetic acid solution will vary depending upon the type of agent beingadded and whether or not one or more agents are added.

The inorganic corrosion inhibitors are preferably present in amountsranging from about 0.01% to 20.0% weight per volume (w/v). Organiccorrosion inhibitors are preferably present in amounts ranging fromabout 0.01% to 5.0% w/v. Phosphates are effective at concentrations inthe range of about 0.01% to about 11.0% w/v.

The surfactants are preferably present in amounts ranging from about0.0001% to about 5.0% w/v. More preferably, the surfactant is present inamounts ranging from about 0.0001% to about 0.5% w/v.

The invention has been described with reference to the preferredembodiment. Obviously, modifications and alterations will occur toothers upon reading and understanding the preceding detaileddescription. It is intended that the invention be construed as includingall such modifications and alterations insofar as they come within thescope of the appended claims or the equivalents thereof.

Having thus described the preferred embodiment, the invention is nowclaimed to be:
 1. A method of cleaning and microbially decontaminating adevice comprising the sequential steps of: (a) positioning the devicewithin a chamber; (b) spraying a washing solution over the device fromnozzles within the chamber to remove soil from exterior surfaces of thedevice; and (c) alternately spraying a microbial decontaminant solutionover the device from a first group nozzles within the chamber urging thedevice in one direction and spraying microbial decontaminant solutionover the device from a second, differently directed group of nozzlesurging the device in another direction to expose and microbiallydecontaminate the exterior surfaces of the device.
 2. The method ofclaim 1, further including between steps (a) and (b): leak testing atleast one internal passage of the device, continuing with step (b) onlyin response to passing the leak test.
 3. The method of claim 1, whereinthe device is an endoscope having internal lumens, step (a) furtherincluding: coiling the endoscope into the chamber; connecting a firstinternal lumen of the endoscope with a liquid supply port and a secondinternal lumen with a leak test port; leak testing the device connectedto the leak test port.
 4. The method of claim 3, further including inresponse to passing the leak test; rinsing the endoscope with water toremove debris; and draining the rinse water.
 5. The method of claim 1,wherein step (b) includes: mixing a cleaner concentrate with water toform the washing solution; concurrently with spraying the endoscopeexterior with the washing solution, circulating the washing solutionthrough at least one interior lumen of the device; and draining thewashing solution.
 6. The method of claim 1, further including after step(b): draining the washing solution; spraying rinse water over theexterior of the endoscope and circulating the rinse water through afirst internal lumen; and draining the rinse water.
 7. The method ofclaim 5, further including: after draining the rinse water, blowingmicrobe-free air through the at least one lumen.
 8. The method of claim1, wherein step (c) includes: mixing a microbiocidal compound with waterto form the microbial decontaminant solution; concurrently with sprayingthe microbial decontaminant solution over the endoscope, circulating themicrobial decontaminant solution through a lumen of the device connectedwith a liquid supply port; and draining the microbial decontaminantsolution.
 9. A method of cleaning and microbially decontaminating anendoscope having at least a first lumen comprising the sequential stepsof: (a) positioning the endoscope within a chamber; (b) spraying awashing solution over the endoscope from nozzles within the chamber toremove soil from exterior surfaces of the endoscope; (c) spraying amicrobial decontamination solution over the endoscope from nozzleswithin the chamber to microbially decontaminate the exterior surfaces ofthe endoscope; (d) flowing a microbial decontamination solution throughthe interior passage from a connector which is releasably connected withan inlet port to the lumen to microbially decontaminate the lumen; (e)passing a fraction of the microbial decontamination solution from theconnector into the chamber, the fraction passing between the connectorand the inlet port of the endoscope adjacent the lumen to kill anymicrobes lodged between the connector and the inlet port.
 10. The methodof claim 9, further including: after step (e), concurrently sprayingsterile rinse water over the endoscope and circulating the sterile rinsewater through the first lumen; and draining the rinse water.
 11. Themethod of claim 10, further including: while draining the rinse water,blowing microbe-free air at least through the first lumen.
 12. Themethod of claim 10, further including after draining the rinse water:spraying the endoscope exterior with alcohol and circulating alcoholthrough the first lumen; and draining the alcohol.
 13. The method ofclaim 12, further including: while draining the alcohol, blowingmicrobe-free air at least through the first lumen.
 14. A method ofcleaning and microbially decontaminating first and second devicescomprising the sequential steps of: (a) mounting the first device withina first chamber and mounting the second device in a second chamber; (b)spraying a washing solution over the first and second devices fromnozzles within the first and second chambers to remove soil fromexterior surfaces of the devices; (c) spraying a microbial decontaminantsolution over the first and second devices from nozzles within the firstand second chambers to microbially decontaminate the exterior surfacesof the first and second devices; (d) spraying a sterile rinse fluid overthe first and second devices from nozzles within the first and secondchambers to rinse the exterior surfaces of the first and second devices;(e) with a common controller, causing steps (b), (c), and (d) to beperformed independently and asynchronously in the two chambers.
 15. Themethod of claim 9, further including: (e) delivering the washingsolution to the lumen of the endoscope to remove soil from the lumen ofthe device; and (f) delivering the microbial decontaminant solution tothe lumen of the endoscope to microbially decontaminate the lumen of theendoscope.
 16. A method of step cleaning and microbially decontaminatinga device with an internal passage, comprising the sequential steps of:(a) positioning the device within a chamber and loosely connecting anend of the device with a port such that an annular passage is definedbetween the end and the port; (b) spraying a washing solution over thedevice from nozzles within the chamber to remove soil from exteriorsurfaces of the device and supplying the washing solution to the port, alarge portion of the washing solution flowing into the internal passageof the device to remove soil from the internal passage of the device anda smaller portion flowing along the annular passage; and (c) spraying amicrobial decontaminant solution over the device from nozzles within thechamber to microbially decontaminate the exterior surfaces of thedevice, supplying the microbial decontaminant solution to the internalpassage of the device to microbially decontaminate the internal passageof the device and concurrently flowing a portion of the decontaminantsolution through the annular passage between the device and a solutionsupply port into the chamber; and (d) spraying a sterile rinse fluidover the device from nozzles within the chamber to rinse the exteriorsurfaces of the device.
 17. The method of claim 15, further including,after step (d): blowing air from nozzles within the chamber overexterior surfaces of the device; and delivering air to the lumen of theendoscope.
 18. The method of claim 17, further including, after step(b): blowing air from nozzles within the chamber over exterior surfacesof the endoscope; and delivering air to the lumen of the endoscope. 19.The method of claim 1, further including, between steps (b) and (c):spraying a pretreatment solution over the device which includes at leastone of a buffering agent and a corrosion inhibitor.
 20. The method ofclaim 19, wherein the pretreatment solution includes a buffering agent,a corrosion inhibitor, and a surfactant.
 21. A method of cleaning andmicrobially decontaminating a device comprising the sequential steps of:(a) positioning the device with an internal passage within a chamber andconnecting the internal passage to a fluid port; (b) spraying a washingsolution over the device from nozzles within the chamber to remove soilfrom exterior surfaces of the device; (c) draining the washing solutionand microbial contamination washed from the device from the chamber toreduce bioload; (d) spraying a pretreatment solution which includes atleast one of a buffering agent and a corrosion inhibitor over the deviceand delivering the pretreatment solution through the fluid port to theinternal passage of the device; (e) after step (d), spraying a microbialdecontaminant solution over the device and delivering the microbialdecontaminant through the fluid port to microbially decontaminate theexterior surfaces and the internal passage of the device; and (f)spraying a sterile rinse fluid over the device from nozzles within thechamber to rinse the exterior surfaces of the device.
 22. The method ofclaim 21, further including, prior to the step of spraying thepretreatment solution over the device: rinsing the device to remove thewashing solution.
 23. The method of claim 21, further including, afterthe step of spraying the pretreatment solution and prior to step (e):combining the pretreatment solution with an antimicrobial decontaminantto form the decontaminant solution.
 24. A method of cleaning andmicrobially decontaminating a device -comprising the sequential stepsof: (a) positioning the device within a chamber; (b) spraying a washingsolution over the device from nozzles within the chamber to remove soilfrom exterior surfaces of the device; (c) spraying a microbialdecontaminant solution over the device from nozzles within the chamberto microbially decontaminate the exterior surfaces of the device anddraining the microbial decontaminant solution; (d) forming a sterilerinse fluid in a water heater by heating unsterile water to a sufficienttemperature to sterilize the water; (e) flowing the sterile rinse fluidfrom the water heater to nozzles within the chamber through fluid lineswhich interconnect the water heater and the nozzles; and (f) sprayingthe sterile rinse fluid over the device from the nozzles to rinse theexterior surfaces of the device.
 25. A method of cleaning andmicrobially decontaminating a device comprising the sequential steps of:(a) positioning the device within a chamber; (b) spraying a washingsolution over the device from nozzles within the chamber to remove soilfrom exterior surfaces of the device; (c) spraying a microbialdecontaminant solution over the device from nozzles within the chamberto microbially decontaminate the exterior surfaces of the device anddraining the microbial decontaminant solution; (d) forming a sterilerinse fluid in a water heater by heating unsterile water to a sufficienttemperature to sterilize the water; (e) removing salts from the sterilerinse water; (f) flowing the sterile rinse fluid from the water heaterto nozzles within the chamber through fluid lines which interconnect thewater heater and the nozzles; and (g) spraying the sterile rinse fluidover the device from the nozzles to rinse the exterior surfaces of thedevice.
 26. The method of claim 1, wherein the decontaminant solutionincludes peracetic acid.
 27. The method of claim 26, further including,during step (c): monitoring the concentration of peracetic acid in thedecontaminant solution.
 28. A method of cleaning and microbiallydecontaminating a device comprising the sequential steps of: (a)positioning the device within a chamber; (b) spraying a washing solutionover the device from nozzles within the chamber to remove soil from thedevice; (c) spraying a microbial decontaminant solution which includesperacetic acid over the device from nozzles within the chamber tomicrobially decontaminate the device; and (d) during step (c),monitoring a concentration of peracetic acid in the decontaminantsolution and, if the concentration of peracetic acid falls below apredetermined level, performing at least one of: terminating the method;signaling that the peracetic acid is below the predetermined level;adding additional peracetic acid to the decontaminant solution; andextending step (c) for a sufficient period of time to microbiallydecontaminate the exterior surfaces at the monitored peracetic acidconcentration.
 29. A method of microbially decontaminating a devicecomprising the sequential steps of: (a) loading the device into achamber through an opening; (b) sealing the opening with a door; (c)moving a latching mechanism from an unlatched position, in which thelatching mechanism allows opening of the door, to a latching position,in which the latching mechanism holds the door in a sealing relationshipacross the access opening latching the door; (d) moving a lockingmechanism from an unlocked position, in which the locking mechanismallows unlatching of the latching mechanism, to a locked position, inwhich the locking mechanism locks the latching mechanism, preventingopening of the door; and (e) after steps (c) and (d), spraying amicrobial decontaminant solution over the device from nozzles within thechamber to microbially decontaminate the exterior surfaces of thedevice.
 30. A method of microbially decontaminating a device comprisingthe-sequential steps of: (a) loading the device into a chamber throughan opening; (b) sealing the opening with a door; (c) moving a latchingmechanism from an unlatched position, in which the latching mechanismallows opening of the door, to a latching position, in which thelatching mechanism holds the door in a sealing relationship across theaccess opening latching the door; (d) after step (c), automaticallysensing that the door is in the latching position; (e) after step (d),moving a locking mechanism from an unlocked position, in which thelocking mechanism allows unlatching of the latching mechanism, to alocked position, in which the locking mechanism locks the latchingmechanism, preventing opening of the door; (f) after step (e), sprayinga microbial decontaminant solution over the device within the chamber tomicrobially decontaminate the device; and (g) controlling the lockingmechanism during step (f) to ensure that the locking mechanism does notmove to the unlocked position until step (f) is complete and after step(f), releasing the locking mechanism permitting the door to beunlatched.
 31. The method of claim 29, wherein the step of moving thelatching mechanism to the latching position includes: pivoting an armconnected with an exterior of the chamber until a roller, rotatablyconnected to the arm, engages an engagement member on an outer surfaceof the door.
 32. The method of claim 31, wherein the step of moving thelocking mechanism to the locked position further includes: engaging thearm with a rod which prevents pivoting of the arm in the lockedposition.
 33. The method of claim 29, further including: automaticallysensing that the locking mechanism is in the locked position prior tocommencing step (e).